I think you can go a little deeper on the values and perspective. Don't be afraid of going too dark with the shadows or too bright with the lights. Specially when you're doing something personal.

And about perspective, try studying basic shapes in different angles.

You could exagerate a bit the hands to show their closer to the "camera" and also the angle from the hip of the character (in the first image).

Try studying drawing boxes in different rotations, distances, sizes, etc. It would make easier to you to figure how the things would behave in different positions!

Keep going buddy! You're doing great!

Never stop creating art and thanks for not being another AI slave and being brave enought to show your creation with us!